Based on an energy release ratebased plasticdamage model and probability density evolution method (PDEM),an investigation of the shortleg shear walls with dual binding beams is conducted on the Pcures,concrete and reinforcement strains,concrete damages and crosssectional internal forces in the frame of stochastic damage mechanics for concrete.Nonlinear stochastic evolution of structures is described through sample tracks,ensemble numerical characteristics and probability density.Multipeaks and multiridges phenomenon appear in probability density function evolution surfaces of the different response level,which roots in couple of randomicity and nonlinearity.It can also be concluded that randomicity and certainty may transform into each other in the process of structural response evolution.